Box 3 & Your Holiday Home In Spain:
What's Really Going On?

Every month we see Dutch owners who have been misinformed about this. Often not through incompetence, but because a Dutch tax advisor knows the Dutch rules inside out while being less familiar with the Spanish side — plus the tax treaty between the two countries. The result: confident statements that turn out to be just slightly wrong. Time to lay it out calmly.

The starting point

Yes, you declare the property in Box 3

Are you a Dutch tax resident and do you privately own a Spanish holiday home? Then that property is part of your wealth in Box 3 and you declare it on your tax return. You don't use the WOZ value for this, but the value in economic transactions: the market value on sale, as of January 1.

The property falls into the category 'other assets'. In 2026, the Dutch Tax Authority calculates this using a deemed return of 6.00% — significantly higher than the 1.28% that applies to savings. Keep that difference in mind; it matters later.

The treaty

Spain has the right to tax, the Netherlands grants relief

The tax treaty between the Netherlands and Spain states that Spain has the right to tax real estate located on Spanish territory. To prevent double taxation, the Netherlands grants a double taxation relief. The value of the Spanish property is then deducted again from your Dutch Box 3 tax.

So directly, you pay (almost) no Dutch Box 3 tax on the property itself. So far, the popular story holds up. But there are two catches.

Catch 1

The relief is a proportional fraction

The Netherlands applies the proportional method with progression reservation. In plain terms: you receive relief proportional to the share the Spanish property represents in your Box 3 return. Because of how the tax-free allowance is divided, in practice the relief regularly falls just a bit short — meaning you still end up paying double tax on a small amount.

Catch 2 — the most important one

Your property makes your savings taxable

The value of the property counts first when determining your total wealth. Because of this, you can end up above the tax-free allowance — and start paying tax on savings that would otherwise have remained untaxed.

And in Spain?

What you'll pay there regardless

• IBI Municipal property tax. Annual, depending on location and value.
• Modelo 210 Non-resident tax (IRNR). Must be filed annually before December 31 — based on deemed personal-use value or actual rental income.
• Patrimonio Wealth tax, varies by region. Comunidad Valenciana: exemption up to €1,000,000 for non-residents.

Update October 2026

New government plans: 2027 already gets more expensive

On 29 September 2026 the Dutch government sent parliament a letter on the future of Box 3. It contains two measures that take effect as early as 2027, still within the current deemed-return system. They are proposals: both chambers of parliament must pass them before 31 December 2026.

What does this mean for a home in Spain? Little changes for the home itself: the tax treaty still applies and the Netherlands still grants the reduction. The effect is once again in catch 2: with the tax-free allowance almost halved, your savings are taxed sooner — and the home pushes you further over the threshold.

From 2028

From deemed return to actual return

The bigger goal remains the Actual Return Box 3 Act (Wet werkelijk rendement box 3). The House of Representatives passed it on 12 February 2026, but the Senate postponed its vote on 30 June 2026. The government is now preparing an amending bill (a novelle). The target date remains 1 January 2028.

For a second home — including a home in Spain — the bill provides for:

• Sale Capital gains tax. The increase in value is only taxed when you sell, not every year.
• Own use A notional addition of 3.35% of the value if you do not rent the home out.
• Rental Actual rental income is taxed; costs such as maintenance are deductible.
• Allowance Tax-free result of €1,000 per person (€1,800 in the original bill). Rate 36%.

According to the letter of 29 September, the government also wants to bring all financial instruments — shares, bonds, options — under capital gains tax in 2028, and the remainder, such as savings and crypto, in 2030.

Treaty & 2028

Why 2028 could actually work out well for Spain

The tax treaty remains the key: Spain may tax Spanish real estate, and the Netherlands must prevent double taxation. Under the current deemed-return system that reduction often falls just short (catch 1). Following the Dutch Supreme Court's Box 3 rulings of June 2024, tax advisors expect that under a system based on actual returns the Netherlands must grant a full exemption for the Spanish home. That would remove the catch.

This is not yet certain. Exactly how the reduction will be calculated in the new system remains to be seen. And the Netherlands and Spain are working on a new tax treaty: officials reached agreement in 2025, but it has not yet been ratified.

• 12 February 2026 — House of Representatives passes the Actual Return Box 3 Act
• 30 June 2026 — Senate postpones its vote
• 29 September 2026 — government letter with new plans for 2027–2030
• Before 31 December 2026 — 2027 measures must pass both chambers
• 1 January 2028 — target start of the new system

Sources (as of 1 October 2026, in Dutch): Rijksoverheid — actual return Box 3 plans · Dutch Senate — bill 36.748 · Deloitte — government letter on the future of Box 3 · Grant Thornton — second home abroad

This article is intended as general information and does not constitute tax or legal advice. Amounts and percentages for 2026 apply to tax year 2026. The figures for 2027 and 2028 are government proposals (as of 1 October 2026) that still need to be passed by both chambers of the Dutch parliament and may change. Always have your situation calculated by a qualified tax advisor with knowledge of both Dutch and Spanish law.